The art is cool. the thwacking animation of the arm also cool. Its a shame I have nothing to hit (at least I cant find any)

Liked the art and mechanics. The collisions were a bit buggy and the player kept falling off the map. Also I was confused and did not realise that the mouse has to be on the object to be destroyed so maybe add an instruction for that 

Not very interesting

Unfortunately the rules were very unintuitive to me :< I had to consult out-of-game description often and I still didn't have a clue how to destroy the rock. The player gets a few mechanics, but without any introduction as to how they work.
I also suggest to be wary of the classic bug risk from player going the other direction (left).